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1.
Small ; : e2405013, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109579

RESUMEN

2D carbon nitride nanosheets, exemplified by g-C3N4, offers significant structural benefits and enhanced photocatalytic activity. Nonetheless, the quantum confinement effect prevalent in nanoscale photocatalysts would result in an enlarged bandgap, potentially restricting the spectral absorption range and impeding improvements in photocatalytic efficiency. Here, a high-performance 2D photocatalyst with an extended spectral response is achieved by incorporating a novel phenol-like structure into the conjugated framework of ultrathin g-C3N4 nanosheet. This novel strategy features targeted pyrimidine doping to create a conjugated carbon zone in heptazine structure, offering a thermodynamically favorable pathway for hydroxyl functionalization during the annealing exfoliation process. Consequently, the π-π* transition energy in the material is significantly decreased, and the active lone pair electrons in phenol-like structure induces a new n-π* transition with notably enhanced absorption from 500 to 650 nm. The optimized material shows a dramatic enhancement in photocatalytic activity, achieving ≈72 times than the activity of bulk g-C3N4, and demonstrating a measurable H2 production rate of 6.57 µmol g-1 h-1 under 650 nm light. This study represents a significant step forward in the strategic design of 2D photocatalysts, with tailored electronic structures that significantly boost light absorption and photocatalytic efficiency.

2.
Adv Sci (Weinh) ; 11(24): e2308322, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493490

RESUMEN

Constructing π-conjugated polymer structures through covalent bonds dominates the design of organic framework photocatalysts, which significantly depends on the selection of multiple donor-acceptor building blocks to narrow the optical gap and increase the lifetimes of charge carriers. In this work, self-bipolarized organic frameworks of single aromatic units are demonstrated as novel broad-spectrum-responsive photocatalysts for H2O2 production. The preparation of such photocatalysts is only to fix the aromatic units (such as 1,3,5-triphenylbenzene) with alkane linkers in 3D space. Self-bipolarized aromatic units can drive the H2O2 production from H2O and O2 under natural sunlight, wide pH ranges (3.0-10.0) and natural water sources. Moreover, it can be extended to catalyze the oxidative coupling of amines. Experimental and theoretical investigation demonstrate that such a strategy obeys the mechanism of through-space π-conjugation, where the closely face-to-face overlapped aromatic rings permit the electron and energy transfer through the large-area delocalization of the electron cloud under visible light irradiation. This work introduces a novel design concept for the development of organic photocatalysts, which will break the restriction of conventional through-band π-conjugation structure and will open a new way in the synthesis of organic photocatalysts.

3.
Cancer Biol Ther ; 5(10): 1285-91, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16969132

RESUMEN

Signaling pathways activated by the Toll-like receptor 4 (TLR4) involve the induction of anti-cancer immunity. While screening for nasopharyngeal carcinoma (NPC) susceptibility genes, we isolated TLR4 and found that the 3'-untranslated region (3'-UTR) of exon 4 contained two polymorphisms that may alter its translation efficiency, potentially leading to NPC. To test this hypothesis, we conducted a hospital-based case-controlled study on NPC patients and cancer-free controls. We determined that the variant allele 11350C and the 11350GC genotype were associated with a significantly increased risk for NPC. We also determined significant differences between the male gender group and the remaining patient cases and controls, and between subjects equal to or younger than 47 years old and the cases and controls. Secondly, we cloned the entire 3'-UTR into a luciferase reporter system, and compared the luciferase activities between the wild-type 3'-UTR construct (WILD) and a construct containing the 11350C variant (MUT). Both constructs caused lower reporter gene activities, as compared to the positive control pGL3-promoter plasmid. Sixty hours after the transfections, the MUT construct reduced the reporter gene activity by 40% compared to that of the WILD construct (P<0.05). Functional analyses of the 11350C variant suggested that the TLR4 3'-UTR is a potent regulator of gene expression, as the mutated TLR4 3'-UTR was associated with decreased mRNA stability, and may down-regulate TLR4 expression resulting in EBV metainfective antiviral immunologic deficits and a high risk of NPC.


Asunto(s)
Regiones no Traducidas 3'/genética , Variación Genética , Neoplasias Nasofaríngeas/genética , Receptor Toll-Like 4/genética , Secuencia de Bases , Cartilla de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Genotipo , Humanos , Masculino , Mutación , Neoplasias Nasofaríngeas/epidemiología , Factores de Riesgo
4.
Cancer Lett ; 211(1): 11-8, 2004 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-15194212

RESUMEN

Epstein-Barr virus (EBV) has been suggested to be involved in pathogenesis of nasopharyngeal carcinoma (NPC). However, EBV infection is ubiquitous, whereas NPC occurs with strong geographic and racial distribution. Whether a substrain of EBV contributes to this phenomenon remains uncertain. Epstein-Barr virus nuclear antigen 1 (EBNA-1) is one of the most frequently detected EBV proteins in NPC tissues. Based on the polymorphism of amino acids at position 487, EBNA-1 is classified into five subtypes: P-ala, P-thr, V-val, V-leu and V-pro. To examine the relationship between subtypes of EBNA-1 and NPC, we determined the subtypes of EBNA-1 in biopsies of NPC, peripheral blood lymphocytes (PBL), and throat washings (TWs) obtained in endemic and non-endemic areas of NPC within China. The results revealed that V-val was the only subtype detected in NPC tissue, whereas three subtypes of EBNA-1, V-val, P-ala, and P-thr, were detected in PBL and TWs irrespective of origin, and mixed infection of V-val and P-ala was also observed. In addition, the variations of V-val derived from biopsies of NPC were identical to those derived from PBL and TWs in the context of N-terminus and C-terminus of EBNA-1. These facts indicate that a substrain of EBV with V-val subtype of EBNA-1 infects NPC preferentially and a susceptibility to a particular EBV isolate in the nasopharynx may exist during development of NPC.


Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/clasificación , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/virología , Secuencia de Bases , Biopsia , Antígenos Nucleares del Virus de Epstein-Barr/genética , Herpesvirus Humano 4/inmunología , Linfocitos/virología , Técnicas de Diagnóstico Molecular , Faringe , Polimorfismo Genético , Irrigación Terapéutica
5.
Zhonghua Yi Xue Za Zhi ; 84(6): 450-5, 2004 Mar 17.
Artículo en Chino | MEDLINE | ID: mdl-15061959

RESUMEN

OBJECTIVE: To evaluate the effect and adverse effects of morphine hydrochloric sustained release for patients with cancer pain. METHODS: A total of 567 patients, 369 males (65.1%) and 198 females (34.9%), aged 65 - 90 with a mean age of 72.6, with cancer pain, 67.4% with severe pain, 28.2% with moderate pain, a and 4.4% with mild pain, that were treated in 25 hospitals from 13 provinces received oral morphine hydrochloric sustained release. The recommended initial dosage was 30 mg every 12 hours, and then the dosage was regulated according to the effects until the ideal anesthesia was achieved. All patients were asked to record the attacks of pain, quality of life, and any side effect of the treatment. RESULTS: The baseline mean pain intensity (NRS) was 7.0 +/- 1.8. On the day 1, 5, 10, 15, 20, 25 and 30, the mean pain scores were decreased to 4.6 +/- 2.6, 2.8 +/- 1.8, 2.7 +/- 1.8, 2.6 +/- 1.7, 2.5 +/- 1.6, 2.3 +/- 1.4, and 2.2 +/- 1.4 respectively (all P = 0.000). The general effective rate on day 30 was 89.8%. The mean dosages were 66 +/- 56 mg/d initially, 84 +/- 64 mg/d (10 - 800 mg/d) on day 15, and 92 +/- 67 mg/d (10 - 800 mg/d) on day 30. On the day 30, 55.1% of the patients received a dosage or= 241 mg/d. Ninety-one point six percent (89.4% - 95.8%) of the patients took morphine orally twice daily. The poor quality of life rate in the patients was 90.5% before treatment, and were 56.8% and 49.6% respectively on the day 15 and day 30 (P = 0.0000 and P = 0.0009). The incidence of side effects was 35.6% on day 1, and 15.1% on day 30. The common side effects were constipation (14.3%), nausea (13.4%), dizziness (3.4%), vomiting (2.8%), drowsiness (0.7%), dysuria (0.4%), mental symptoms (0.2%), and respiratory depression (0.2%). Sixty-eight point four percent of the patients preferred continuation of sustained release morphine hydrochloride treatment. CONCLUSION: Oral treatment with sustained release morphine hydrochloride for patients with cancer pain is effective, safe, and convenient, and can improve the quality of life. Sustained release morphine hydrochloride is worth recommending as a first-line drug for the treatment of patients with moderate to severe cancer pain, and the usually dosage is 120 mg or less per day.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Morfina/uso terapéutico , Neoplasias/complicaciones , Dolor/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , China , Preparaciones de Acción Retardada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morfina/administración & dosificación , Morfina/efectos adversos , Dolor/etiología , Satisfacción del Paciente , Calidad de Vida , Comprimidos , Resultado del Tratamiento
6.
Nat Genet ; 31(4): 395-9, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12118254

RESUMEN

Nasopharyngeal carcinoma (NPC) occurs with high frequency in Asian populations, especially among people of Cantonese ancestry. In areas with high incidence, NPC clusters in families, which suggests that both geography and genetics may influence disease risk. Although the HLA-Bw46 locus is associated with increased risk of NPC, no predisposing genes have been identified so far. Here we report the results of a genome-wide search carried out in families at high risk of NPC from Guangdong Province, China. Parametric analyses provide evidence of linkage to the D4S405 marker on chromosome 4 with a logarithm of odds for linkage (lod) score of 3.06 and a heterogeneity-adjusted lod (hlod) score of 3.21. Fine mapping with additional markers flanking D4S405 resulted in a lod score of 3.54 and hlod score of 3.67 for the region 4p15.1-q12. Multipoint nonparametric linkage analysis gives lod scores of 3.54 at D4S405 (P = 5.4 x 10(-5)) and 4.2 at D4S3002 (P = 1.1 x 10(-5)), which is positioned 4.5 cM away from D4S405. When Epstein Barr virus antibody titer was included as a covariate, the lod scores reached 4.70 (P = 2.0 x 10(-5)) and 5.36 (P = 4.36 x 10(-6)) for D4S405 and D4S3002, respectively. Our findings provide evidence of a major susceptibility locus for NPC on chromosome 4 in a subset of families.


Asunto(s)
Carcinoma/genética , Cromosomas Humanos Par 4 , Ligamiento Genético , Neoplasias Nasofaríngeas/genética , Adulto , Pueblo Asiatico/genética , Carcinoma/virología , China , Cromosomas Humanos Par 12 , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Genoma Humano , Herpesvirus Humano 4 , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/virología , Linaje , Recombinación Genética
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 19(3): 479-82, 2002 Sep.
Artículo en Chino | MEDLINE | ID: mdl-12557528

RESUMEN

Hemolysis caused by blood pumps is a very important characteristic. In vitro hemolysis test circuits were constructed to operate the model I centrifugal pump, the model II axial flow pump, the magnetic coupling pump and the model I & II spiral mixed pump. The output of all pumps was set at flow 5 L/min, an average pressure of 100 mmHg. Experiments were conducted for 4 hours at room temperature(25 degrees C) with 500 ml fresh anticoagulant sheep blood. Blood samples were taken for plasma free-hemoglobin measurement, and the change in temperature at the pump outlet port was measured during the experiment. Calculate the normalized index of hemolysis (NIH). The results showed that there was no relationship either between the pump rotational speed and the NIH in five types of blood pumps, or between change in temperature at the pump outlet port and NIH. The dynamic fluid field caused by pump design and structure could be the main cause of blood damage.


Asunto(s)
Corazón Auxiliar/efectos adversos , Hemólisis , Animales , Velocidad del Flujo Sanguíneo , Estudios de Evaluación como Asunto , Técnicas In Vitro , Ovinos , Temperatura
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